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December, 1909 Delaware and HE trials of the two. latest battleships. for the United States navy again serve to draw attention to the ap- parent anomaly in results when com- parisons are between turbine and reciprocating engine driven ships. It is the case of the Lusitania over again, That the propeller efficiency of the reciprocating engine driven ship is higher than that of the tur- bine is not debatable; hence the steam consumption per effective horsepower is lower, although, measured in terms of shaft horsepower, the turbine may appear to have somewhat the best of 'the argument. The trials show both ships to be highly efficient ma- chines and the results as nearly alike as could possibly be expected, and considering each ship as a whole the performance at the higher speeds probably agreed as closely as though the two ships had been identical in all respects and from the. hands of the same builders, as an_ inspection of numerous other trials of identi- cal ships will bear witness. The ships... are...510) tt.0 in leneth, 85. tt beam, trial draught 27 ft. The North Dakota was built by the Fore River Shipbuilding Co., Quincy, Mass., and the Delaware by the Newport News Shipbuilding & Dry Dock Co., New- port News, Va. Both companies are proud of their product, and the press has. been filled with conflicting state- ments regarding the trials. THe Re- view is able to present the statements of both companies. drawn Statement of the Fore River Co. THE Marine REVIEW North Dakota further noted that the higher top notch speed of the North Dakota per- mits her to reach her destination quicker than the Delaware. "The above speeds and coal con- sumption are determined by the Trial Board of the Navy Department. "The steaming 'radii of the ves sels are computed from these offi- cial figures and from the fuel capa- city of the vessels. As the fuel capa- city of each vessel is the same, and as the coal consumption of the North Dakota is less, it is quite evident that her steaming radius is greater. There can be no. better criterion of the actual abilities of two vessels than shown by the results of the offi- cial acceptance trials, COMPARISON, North Dakota. Delaware. Fastest run over measured MALE ee a, dan ees 22525 21.98 Average of five high runs.. 21.83 21.44 Full power trial speed.... 21.64 21.56 Full power trial, H. P....31,400 28,600 Full power trial, coal con- . sumption, tons, per day. 583 578 19-knot trial, coal consump- tion, tons, per -daya..... 295 315 12-knot trial, coal consump- tion; .tons;. per. day ....2.) 2105 111 "An inspection of the above table shows at once that the North Dakota developed a higher speed than the Delaware on all the high speed trials and has the highest speed on the measured mile, the highest average for the five high speed runs and de- veloped a higher speed during the full power trials. "The table also shows that the North Dakota was the most eco- -nomical vessel on both nineteen and twelve knot runs, burning twenty TRIALS OF NORTH DAKOTA. + 3 hoursof 24-hour trial 24-hour trial full power trial. at 19 knots. at 12 knots. S OMOPAMO i GDOOU ois ule see ence a oor wena ase Male 21.64 *19.24 12.05 ne fr Aenea aus ner Oe a ee 280.4 231.9 143.2 Shatt: Hi Patek (main turbines ka ae ee ie ee aes 31,400 *16,710 3,800 1 Pe of engineers. AUxIIATICS 3.4 seuclai cares 6 occas - 1,100 660 é 400 Water rate of main turbines only ......... ea 13.6 14.11 20.5 ineer's urposes, based on to- ee H oo rem RO eee 13.96 "15.29 283 @oal used, "pounds. per hour)... .00. 16. oe eee 54,400 27,550 ae Coal used, tons per 24 hours' ............. teenies 5e80 4 295.3 ee Coal per hour per shaft horsepower of turbinés...... 1.74 71.65 a Coal pér hour per horsepower for total horsepower.... 1.68 1.58 ' Coal per hour of equivalent I. H. P., based on 8 per wikis a cent friction for reciprocating engine .......+... 1.55 a 4 . ; om STANDARDIZATION TRIAL. ke Highest speed on mile, uncorrected for tide, knots...-..+sssssesserseerersetenerens Rig See Mean of five high runs, ~ Knotess. 00 cee eee ee i er meray Et oar oe omy 8 5 RoR. ME foe 21 ble hs ae oe en ek Oe ee ice ee emesis aos sens Roo Pie Mi for 19) Knots. eee eae a Pe ee a ea cee RPMS for 42 lente ys ccs ve rb a hen oe a neo = oie ai eerie eta © tye as RO Rd 2 8 a ne > Maximum shaft horsepower developed on mile hg 6 0b. 0: 6 1b, be 0056 OTR Oe Pe 1801 4:0 V6 (08 8.98 Teele 8 8 8 Oe "Tt should be noted that the coal consumption of the North Dakota on the high speed test is for a some- what higher speed than the Delaware, and that for small increases of speed near the maximum the coal consump- tion rapidly increases. It should be tons less per day on the nineteen knot run and six tons less per day on the twelve knot run, and on the full speed test, although the coal con- sumption of the Delaware is slightly less the speed of the North Dakota is higher." spéed* of the $31 Statement by the Newport News Co. "During the standardization trials of the Delaware on Oct. 23 the fastest run on the measured mile was 21.664 knots. The average of the two highest runs over the measured mile was 21.623 knots. The average speed for the five high speed runs was 21.444 knots. The speed one way over the measured mile during standardization runs is no indication of the ship's speed, on account of the varying influences of the tide. These standardization runs of the Delaware were made at as nearly uniform speeds as_ possible in order to secure reliable curves, and the ship was not forced during the runs. Trials of Delaware. FULL. SPEED, FOUR-HOUR. TRIAL, OCT s. 23,1900; Speed, "knots. 230.5 pe alee ool ote ege ulues 21.563 SE Bye ok eeu wee eee 28,578 Coal consumption, per hour, tons... 24.05 Steam consumption of main engines per: He OPS per hour, 1bs..0y 2 13.12 Steam consumption for all purposes per une P. perss hours lbs, oo ie 5 25.6 "The speed for the twenty-four hour nineteen knot trial was 19.225 knots and for the twenty-four hour twelve. knot trial was 12.275 knots. In order that a cOmparison between 'the per- formances of the two ships may be made on the same basis we give be- low the principal data for the Dela- ware at even speeds of 21, 19 and 12 knots respectively :-- AT 21 KNOTS. Coal, t0ns.. per shout. soc ee seen 19.2 To Pa, ca eee ee tere eae 23,600 Steam consumption, main engine, pe THR Sper hours Wbs.iai ae cen nS 13.05 Steam consumption, all purposes, per Tea Py per nour. Ibs ise 6 os are 14.5 Amount of steam used by main en- e gies per: Hour, tons ......s...00. 137.5 Amount of steam used by all machin- ery. per hour, tons: so. oe. 92S AT 19 KNOTS. Co: li tons.per ) Nouri cas ss es 11.6 I, "HL Pe Be Eats FAG tant ott a 8 14,560 Steam consumption, main engines, per ie OH Pa per. hor shoe ess se 12.92 Steam consumption, all purposes, per I, H. P. per hour, Ibs...... Seep 14.85 Amount of steam used by main en- gines per hour, tons .........++. " 84 Amount of steam used by all machin- ery per hour, tomsS ......eeseeeeees 96.6 AT 12 KNOTS. tons, per Hour. ......ee eee toe 4.3 Coe ae -- RO GG Case Sigs e <p sue 58,020 Steam consumption, main engines, per TI. H. P. per -hour, Jbs......... ee 15,7 Steam consumption, all purposes, per J. H. Py per hour, lbs. ..../. pees 21.6 Amount of steam used by main en- gines per hour, tons............ a 24.6 Amount of steam used by all machin--- ery per hour, tomS ........++.s0. 34.0 "During the trials of the Delaware the feed water heaters were not in use owing to a leak in one of the joints. This necessitated pumping cold water into the boilers during the trials and caused an increase in the amount of coal consumed, "The Delaware and the North Da- « a